Technical Field
This invention relates to Seismic base isolation and energy dissipation devices for structures. The present invention will be placed between a structural load and its foundation.
Background Art
Many devices and equipment systems exist to reduce the seismic ground motion energy that is transmitted to a structure when an earthquake event occurs. Many of these earthquake motion protective systems fall in the category of base or foundation isolation systems, as does the present invention. Some of the most complex units are those that reply on pendulum like motion where gravity supplies the force to dampen the energy and restore the supported load to its original point of equilibrium and stability. A common draw back of most prior art of these base isolation systems are they are very expensive and complex. Also these systems require uncommon and difficult to manufacture materials and some require advanced technologies in the fields of electronics, computers and metallurgy. Yet another drawback is many only allow movement in two perpendicular directions. Many of these pendulum systems require constant monitoring and are costly to maintain or need replacement after a seismic event. The engineers designing the older pendulum systems often focus all the seismic energy on to a few pivotal moving parts creating a lot of stress on these complex parts, making it very hard to predict their reliability or extend their application to support larger structures, also limiting the amount of ground movement they could handle. The present invention overcomes many of these drawbacks by introducing a new design that will not focus the seismic motion to a few unique and often over loaded parts. The present invention will scale easily to support large size structural load while remaining the same design or shape, except for using thicker materials and greater dimensions to accommodate larger loads. The present invention will reduce or prevent structural damage and it will eliminate all the previously sited short comings of high cost and mechanical complexity, and limited range of applications also the present invention will be easy to assembly, easy to install and will require very little maintenance.